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Adsorption of β-naphthalenesulfonic acid/sulfuric acid from their solution by weakly basic resin:equilibrium

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Journal of Environmental Sciences 2005年第4期17卷 646-649页

作者： chang-hai SHIPeng-fei DepartmentofChemicalEngineering ChangchunUniversityofTechnologyChangchun130012China DepartmentofAppliedChemistry HarbinInstituteofTechnologyHarbin150001China

Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA) and sulfuric acid (H_2SO_4) from their solution at 25℃ onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The ideal adsorbed solution theory(IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.

关键词： β-naphthalenesulfonic acid adsorption weakly basic resin

Effect of Compressive Stresses on Microstructure of Scales Formed on Pure Iron During Continuous Air Cooling

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Journal of Iron and Steel Research International 2010年第2期17卷 27-30页

作者： ZHOU chang-hai MA hai-tao WANG Lai School of Materials Science and Engineering Dalian University of Technology Dalian 116085 Liaoning China

The microstructure development of oxide scale on pure iron under the mutual action of compressive stress and cooling conditions was investigated. Oxide scale structure was examined by optical microscopy （OM） and scanning electron microscopy （SEM）. It was found that oxide scale formed under normal cooling conditions had a struc ture mainly consisting of an outer magnetite and an inner wustite layer. When a compressive stress was applied, numerous magnetite precipitates formed within wustite layer homogeneously at starting cooling temperature of 900 ℃, and the wustite layer in the scale was transformed into a mixture of mostly magnetite/iron eutectoid and magnetite layer at starting cooling temperature of 700 ℃. The wustite decomposition and precipitation of magnetite in wustite under compressive stress were discussed.

关键词： compressive stress oxide scale wustite magnetite cooling

Deterioration behavior of c-Si solar cell decorated with silver nanoparticles

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Rare Metals 2019年第2期38卷 136-141页

作者： Xuan-Min Zhu hai-Mei chang hai-Zheng Tao Xiu-Jian Zhao State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology

Silver nanoparticles(AgNPs) with well-distributed sizes were prepared by magnetron sputtering on slides and crystalline silicon(c-Si) solar cell following by annealing at different temperatures. The morphologies,optical and photovoltaic performance were investigated in detail. The spectroscopic result shows that two resonance peaks resulting from coupling effect among neighboring particles are difficult to obtain by other chemical *** photovoltaic performances reveal that the solar cells decorated with AgNPs significantly are degraded, including a maximal decrease of 20.4 % in short-circuit density and 53.9 % in energy conversion efficiency. The lowest efficiency achieved is 5.85 % for c-Si solar cells with AgNPs annealed at 500 ℃. The deterioration should result from the synergetic effect of the intrinsic absorption of single particle and coupling absorption between neighboring particles.

关键词： Magnetron sputtering Silver nanoparticles Anneal Plasmon resonance Crystalline silicon solar cell

Asymptotic analysis for transmission capacity of wireless Ad-hoc networks

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 22-26页

作者： CHEN chang-hai YIN chang-chuan YUE Guang-xin Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article puts forward a new solution to the bound of the outage probability and transmission capacity of Ad-hoc networks. For the proofs of the upper and lower bounds are too complex, a much easier way is introduced to get the same results, and by using Taylor series, the asymptotic bound is derived. By comparing with the simulation results, we found that the asymptotic bound is sufficient accurate when the network parameters are selected properly, and is tighter than the upper and lower bounds.

关键词： Ad-hoc transmission capacity lower and upper bounds asymptotic bound

Properties and Structural Optimization of Pulverized Coal for Blast Furnace Injection

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Journal of Iron and Steel Research International 2011年第3期18卷 6-12页

作者： JIANG hai-bing chang Jian LI Jing School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The properties of mixed coals were studied on the basis of known various properties of the injecting coals in the *** structure of the injecting coals was optimized and put into practical *** was found that the ignition point was lowered with mixed coals,however,both combustibility and grindability were improved,and explosibility of the mixed coals were decreased as ***,mixed coals injection not only can improve the amount of the injecting coals greatly,but also improve the economical and technical indexes of the blast furnace.

关键词： blast furnace pulverized coal property injection

changes of Reactive Oxygen Species and Related Enzymes in Mitochondrial Respiration During Storage of Harvested Peach Fruits

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Agricultural Sciences in China 2011年第1期10卷 149-158页

作者： KAN Juan WANG Hong-mei JIN chang-hai College of Food Science and Engineering Yangzhou University Yangzhou 225127 P.R.China

Peach fruits [Prumus persica （L.） Batsch, cv. Yuhuasanhao] were used as materials to investigate the changes of reactive oxygen species （ROS） and related enzymes in mitochondria respiration during storage and then their influence on senescence of harvested Peach fruits was studied. The results showed that low temperature （5℃） strongly inhibited the reduction of firmness and the increase in respiration rate. During storage at ambient temperature （20℃）, ROS had a cumulative process while malondialdehye （MDA） content continued to increase in associated with enhanced membrane lipid peroxidation. Lipoxygenase （LOX） activity was strongly inhibited under the low temperature condition. The activities of succinic dehydrogenase （SDH）, cytochrome C oxidase （CCO）, and Ca^2＋-ATPase declined to a certain extent at ambient temperature, while they showed higher activities at low temperature, which may be related to lower membrane lipid peroxidation at low temperature. Higher Ca^2＋ content at ambient temperature may be responsible for impairment of mitochondrial function, thus, leading to fruit senescence. The results showed that under low temperature condition, the low accumulation of ROS and the low level of membrane lipid peroxidation could maintain the function of mitochondria that would help to delay the senescence of peach fruits. These suggested a close relationship existed between ROS metabolism and mitochondrial respiration. It can be inferred that the low temperature helps to delay senescence of peach fruits via suppression of ROS and related enzymes, maintain better homeostasis of Ca^2＋ in mitochondria and thus better mitochondrial functions.

关键词： peach fruits ripening active oxygen enzymes related to mitochondria respiratory metabolism

A new analytical model for the low-velocity perforation of thin steel plates by hemispherical-nosed projectiles

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Defence Technology（防务技术） 2017年第5期13卷 327-337页

作者： chang-hai CHEN Xi ZHU hai-liang HOU Xue-bing TIAN Xiao-le SHEN Department of Naval Architecture Engineering Naval University of EngineeringWuhanHubeiPR China Lvshun Proving Ground Naval Unit No.91439Dalian 116041PR China

Ballistic experiments were conducted on thin steel plates that are normally impacted by hemisphericalnosed projectiles at velocities higher than their ballistic limits. The deformation and failure modes of the thin steel plates were analyzed. A new method was proposed according to the experimental results and the perforation phenomenon of the thin steel plates to determine the radius of the bulging region. In establishing this new method, a dynamic method combined with the plastic wave propagation concept based on the rigid plastic assumption was adopted. The whole perforation process was divided into four consecutive stages, namely, bulging deformation, dishing deformation, ductile hole enlargement, and projectile exit. On the basis of the energy conservation principle, a new model was developed to predict the residual velocities of hemispherical-nosed projectiles that perforate thin steel plates at low *** results obtained from the theoretical calculations by the present model were compared with the experimental results. Theoretical predictions were in good agreement with the experimental results in terms of both the radius of the bulging region and the residual velocity of the projectile when the strain rate effects of the target material during each stage were considered.

关键词： Ballistic impact Thin steel plate Perforation Low velocity Hemispherical-nosed projectile

Nature's disguise:Empirical demonstration of dead-leaf masquerade in Kallima butterflies

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Zoological Research 2024年第6期45卷 1201-1208页

作者： Zeng-Tao Zhang Long Yu hai-Zhen chang Shi-chang Zhang Dai-Qin Li State Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioural Ecology&EvolutionSchool of Life SciencesHubei UniversityWuhanHubei 430062China Wuhan Wuluolu Experimental Junior High School WuhanHubei 430070China Department of Biological Sciences National University of SingaporeSingapore 117543Singapore

Animals deploy diverse color-based defenses against predators,including crypsis,mimicry,aposematism,and *** crypsis,mimicry,aposematism have been extensively studied,the strategy of masquerade-where organisms imitate inedible or inanimate objects such as leaves,twigs,stones,and bird droppings-remains comparatively underexplored,particularly in adult *** Indian oakleaf butterfly(Kallima inachus)exemplifies this phenomenon,with its wings resembling dead leaves,providing a classic example of natural *** it has long been postulated that these butterflies evade predation by being misidentified as dead leaves,direct experimental evidence is *** the current study,using domestic chicks as predators,we manipulated their prior experience with dead leaves(model objects)while maintaining constant exposure to butterflies to test whether dead-leaf masquerade provides a protective advantage by preventing *** showed a marked delay in the initiation of attacks by chicks familiar with dead leaves compared to those with no prior exposure or those exposed to visually altered *** with prior dead-leaf experience required a similar amount of time to attack the butterflies as they did to attack dead *** findings provide the first empirical demonstration of dead-leaf masquerade in Kallima butterflies,shedding light on its evolutionary *** study highlights the effectiveness of masquerade in inducing the misclassification of butterflies as inanimate objects,showcasing the precise mimicry achieved by these organisms when viewed in isolation from the model *** study advances our understanding of the evolution of masquerade and its role as a potent antipredator strategy in nature.

关键词： Antipredator defense Camouflage Deadleaf butterfly Masquerade Natural selection Visual recognition

Effect of forging temperature on the microstructures and mechanical properties of the SiC_p/AZ91 magnesium matrix composite

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 99-105页

作者： Kun WU Kunkun DENG hai chang Yewei WU Xiaoshi HU Mingyi ZHENG School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

In this paper, 10 vol. pct SiCp/AZ91 magnesium matrix composite was fabricated by stir casting technology. The ingots were forged at temperatures of 320, 370 and 420 ℃, respectively. XRD, OM and SEM were used to characterize microstructure of the＇composites. It was shown that the clusters of particles in the as-cast composite were largely eliminated, and that the tensile strength was improved obviously.

关键词： Magnesium matrix composite Forging Mechanical properties